Cuban and U.S. flags are seen on balconies in Havana on March 20.

Renewed diplomatic relations between the U.S. and Cuba may be good for Americans who want to vacation in Havana — but some fear it could be bad for Cubans migrating overseas.

Thousands of Cubans, the most in nearly a decade, are fleeing their homes, fearing the new push for normalcy between the two countries could put an end to lax immigration policies that essentially grant amnesty to any Cuban who made it to American soil.

“The perception is that the time is now. Given all that is going on, I could see how that perception would exist,” said Coast Guard Capt. Mark Gordon.

Those fears are largely unfounded — but they’ve still prompted tens of thousands of Cubans to flee since President Obama announced in late 2014 that the U.S.’s Cold War standards for dealing with the communist nation would slowly warm to a more diplomatic relationship.

The rush to leave has led to the highest number of people trying to make the dangerous sea crossing in the past eight years, according to internal Homeland Security Department documents obtained by The Associated Press.

Currently — and for the foreseeable future — Cubans can get permanent resident status after living in the U.S. for a year and can later become a citizen as part of the decades-old Cuban Adjustment Act.

U.S. President Barack Obama and Cuba's President Raul Castro shake hands during their first meeting on the second day of Obama's visit to Cuba.

(JONATHAN ERNST/REUTERS)

Basically: If a Cuban can make it to U.S. land, he or she is allowed to stay.

No other immigrant community is afforded the same on-arrival treatment. Most foreigners trying to come to the United States without a visa try to cross the Mexican border illegally, and typically are arrested and face deportation.

The special treatment for Cubans has long been a draw, but attempts to get to the U.S. by sea have recently reached worrisome levels.

During 2015, more than 4,400 Cubans set out for the U.S. by sea — a 20% increase over the previous year, according to Coast Guard figures.

Would-be immigrants caught at sea are returned to Cuba, so the rush has made people more desperate, with some actually wounding themselves with knives or guns in the hopes they will be taken to a hospital in the U.S. instead of sent back. Others try to flee rescuers and refuse life jackets.

Light clouds hang over the historic Old Havana neighborhood on March 20.

(Chip Somodevilla/Getty Images)

A man walks past a painting of the late revolutionary hero Ernesto "Che" Guevara in Havana, Cuba.

(UESLEI MARCELINO/REUTERS)

Many Cubans fear new relations between the U.S. and Cuba will make migrating more difficult.

Since October 2014, U.S. Customs and Border Protection has processed nearly 75,000 Cubans who arrived at ports of entry. During the same period, more than 131,800 families and unaccompanied children, mostly from Central America, have been apprehended at the border in the Rio Grande Valley.

The Cubans were allowed into the United States while the families and children were almost all ordered to appear in immigration court.

Though migration has been a topic of discussion between the two countries, changes to U.S. immigration laws have not been formally proposed by either government.